projecting a flat image onto a spherical surface

E

EddieM

• 29 Sep 2018

• #1

Not sure if this is the right forum but here goes. I want to project an image from a flat source onto a spherical object. I suppose there are 2 ways, manipulate the original image via something like Photoshop or use a special lense, any ideas. TIA.

 

O

OwainDIYer

Joined

5 May 2010

Messages

4,559

Reaction score

721

Location

Stirlingshire

Country

• 29 Sep 2018

• #2

To fully cover a sphere you will need multiple projectors (as the sun can't shine on both sides of the moon) and some projector mapping/warping software to stitch the projectors together and bend the image.

http://www.blue-room.org.uk/index.php?showforum=41

may have some ideas

 

bernardgreen

Joined

3 Nov 2006

Messages

28,063

Reaction score

3,277

Location

Bedfordshire

Country

• 29 Sep 2018

• #3

Projects from inside the plinth under the sphere, probably very expensive.

 

E

EddieM

• 30 Sep 2018

• #4

I think I should have been more specific, I want to accurately project a flat image onto a curved surface, a pumpkin if you must know

 

S

Sandtree

Joined

10 Mar 2017

Messages

38

Reaction score

3

Country

• 4 Oct 2018

• #5

If you are only going to be projecting a face on a pumpkin or such then you may not need to correct for the shape. Maybe have a look at the likes of https://atmosfx.com/pages/prop-mode who do videos for projecting onto a manakin to look like ghosts etc.

 

Tigercubrider

Joined

22 Jul 2016

Messages

5,876

Reaction score

1,081

Country

• 4 Oct 2018

• #6

as it's a one off you are best to do this in photoshop
In Theatre you'd use QLab pro and warp the video - it needs a Mac and can distort an image to project on a weird surface.

Basically set up the computer, projector and pumpkin and then distort the projection image via photoshop to fit.
A smaller pumpkin will be more curved than a big one.
Distance is important to maintain.